1. Application of differential staining techniques for chromosome analysis. 2. Studies of the inheritance of several autoimmune immunological trits including antibodies cytotoxic for T lymphocytes and reactive with single stranded DNA and chromosomal hyperdiploidy. 3. Use of flow cytometry in the analysis of aneuploid cells. 4. Analysis of radiation chimeras to determine if autoimmune stem cells have increased repopulation potential. 5. In vivo cell cycle analysis of polyclonal B-cell activation by flow cytometric techniques. 6. The use of recombinant inbred lines to determine the presence of an underlying defect - giving rise to autoimmune disease. 7. Syngeneic bone marrow transfers to study fate of transferred marrow.